product_list =[
    ('华为p30',3800),
    ('Mac Pro',16000),
    ('Crabs',88),
    ('Bike',800),
    ('watch',100050),
    ('head first python',128),
    ('book',100),

    ]
shopping_car = []

zhifubao = input("请输入支付宝余额")
#购物车商品选择
if zhifubao.isdigit():
    #检测是否输入的是数字，不然会报错
    zhifubao = int(zhifubao)
    while True:
        for item in product_list:
            print(product_list.index(item),item)
        choice = input("请输入商品编号")
        #商品的选择
        if choice.isdigit():
            choice = int(choice)
            if choice >=0 and choice <8:
                if zhifubao >= product_list[choice][1]:
                    zhifubao = zhifubao - product_list[choice][1]
                    shopping_car.append(product_list[choice])
                    print("你把商品%s添加到购物车，你的支付宝余额是%s"%(product_list[choice][0],zhifubao))
                else:
                    print("支付宝余额不足，请重选")
            else:
                    print("没有这个商品，请重选商品")
        elif choice =="q":
            print("--购物清单--")
            for item in shopping_car:
                print(item)
            print("你的支付宝余额%s"% zhifubao)
            break
        else:
            print("按q退出程序")
else:
    print("请输入数字金额")
